Fix clean build from VS
Fix clean build from VS

Resolves #383

The Packages project needs to build after its dependencies
- WebJobs.Script
- WebJobs.Script.Extensibility
- WebJobs.Script.WebHost

This fix explicitly adds these dependencies so VS will build the projects in the right order.

Azure/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,Azure/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,Azure/azure-webjobs-sdk-script,Azure/azure-webjobs-sdk-script